<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
  <style>
    .f1{
      font-size:12px;

    }

    .f2{
      font-size:12px;
      transform: scale(0.7,0.7);
    }

    p{
        font-size:20px;
        color:blue;
    }
  </style>
</head>
<body>
<p class = "f1">this is a book  测试中</p>
<p class = "f2">this is a book  测试中</p>
<script>
  function logA() { console.log('A') }
  function logB() { console.log('B') }
  function logC() { console.log('C') }
  function logD() { console.log('D') }


  // logA();
  // setTimeout(logB, 0);
  // Promise.resolve().then(logC);
  // logD();

  console.log('script start');

  setTimeout(function () {
    console.log('setTimeout');
  }, 0);

  Promise.resolve()
          .then(function () {
            console.log('promise1');
          })
          .then(function () {
            console.log('promise2');
          });

  console.log('script end');

</script>
</body>
</html>